Novel Assessment of Keratinocytes for NER Assay Use
One of the most essential cellular DNA repair pathways, nucleotide excision repair (NER), is crucial to the prevention of cancer and early onset aging, in particular neurodegeneration. Mutation-induced reductions in NER capacity may cause debilitating conditions such as Xeroderma Pigmentosum and are a matter of great concern. Consequently, assays of cellular NER in response to UV-induced DNA damage have been optimized to further understand NER capacity and to identify NER-deficient individuals. However, keratinocytes, the cells most frequently exposed to NER-inducing UV radiation, are infrequently assessed using NER assays. Here we show that keratinocyte NER capacity is not consistent with fibroblast and lymphocyte NER capacity within individuals. Although keratinocytes tend to display reduced NER capacity compared to fibroblasts from the same individual, the magnitude of this difference in NER capacity is not consistent. These results suggest that measurement of keratinocyte NER response may yield unique information compared to assays of other cell types. Given this, despite the difficulty of culturing keratinocytes, future NER assays may benefit from incorporating keratinocyte analysis.